Solid-State Electron Transport across Azurin: From a Temperature-Independent to a Temperature-Activated Mechanism

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• 作者：Lior Sepunaru ; Israel Pecht ; Mordechai Sheves ; David Cahen
• 刊名：Journal of the American Chemical Society
• 出版年：2011
• 出版时间：March 2, 2011
• 年：2011
• 卷：133
• 期：8
• 页码：2421-2423
• 全文大小：699K
• 年卷期：v.133,no.8(March 2, 2011)
• ISSN：1520-5126

文摘

The temperature dependence of current鈭抳oltage values of electron transport through proteins integrated into a solid-state junction has been investigated. These measurements were performed from 80 up to 400 K [above the denaturation temperature of azurin (Az)] using Si/Az/Au junctions that we have described previously. The current across the 3.5 nm thick Az junction was temperature-independent over the complete range. In marked contrast, for both Zn-substituted and apo-Az (i.e., Cu-depleted Az), thermally activated behavior was observed. These striking temperature-dependence differences are ascribed to the pivotal function of the Cu ion as a redox center in the solid-state electron transport process. Thus, while Cu enabled temperature-independent electron transport, upon its removal the polypeptide was capable only of supporting thermally activated transport.